Hair-clipping cutter system

ABSTRACT

Displacement device for a hair-clipping cutter system for a dryshaving apparatus, the hair-clipping cutter system being displaceable by means of a sliding knob between an extended position and a retracted position in the direction of shifting of the sliding knob. The stroke of the sliding knob is smaller than the shifting distance of the cutter system.

United States Patent [191 de Boer et al.

[ Dec. 25, 1973 HAlR-CLIPPING CUTTER SYSTEM Inventors: Jan de Boer;Petrus Jozephus Johannes Vaes, both of Oliemolenstraat, Drachten,

Netherlands I Assignee: U.S. Philips Corporation, New

York, NY.

Filed: May 3, 1971 Appl. No.: 139,569

Foreign Application Priority Data May 28, 1970 Netherlands 7007686 US.Cl 30/34.], 30/43.], 74/110 Int. Cl. B26b 19/20, F1611 21/44 Field ofSearch 30/34.], 43.1, 20l,

[56] References Cited UNlTED STATES PATENTS 2,917,824 l2/l969 Brauss30/43.! X 3.552.007 l/l97l Yamada Primary Examiner-Othell M. SimpsonAssistant Examiner-Gary L. Smith Attorney-Frank R. Trifari [5 7]ABSTRACT Displacement device for a hair-clipping cutter system for adry-shaving apparatus, the hair-clipping cutter system beingdisplaceable by means of a sliding knob between an extended position anda retracted position in the direction of shifting of the sliding knob.The stroke of the sliding knob is smaller than the shifting distance ofthe cutter system.

6 Claims, 6 Drawing Figures PATENTEDUEB25I975 3.780.434

' sum 3 or 3 INVENTORS JAN DE BOER PETRUS J.J VAES I LL L AGE THAIR-CLIPPING CUTTER SYSTEM The invention relates to a hair-clippingcutter system of a hair-clipping device, in particular of ahair-clipping device for a dry-shaving apparatus, which cutter system isdisplaceable by means of a sliding knob through a distance between anextended position and a retracted position of the cutter system, duringwhich'displacement the sliding knob operates at least one pin which ismovable in the direction of displacement of the cutter system and iscoupled thereto in a manner such that the distance through which thesliding knob is shifted to produce this displacement of the cuttersystem is not equal to the distance through which the cutter system isdisplaced. Such an arrangement is described in US. Pat. No. 3,413,718.

It is an object of the invention to provide a haircutting device, thecutter system of which in the operative position is readily displaceableover the area of the skin on which the hair is to be clipped without theuser being inconvenienced by parts of the casing of the apparatus. Thisis of particular importance for dryshaving apparatus provided withhair-clipping devices in which in the known apparatus, the cuttingmembers of the hair-clipping device generally protrude from the wall ofthe apparatus casing through a small distance only.

The invention is characterized in that the distance through which thecutter system is displaced is greater than the distance through whichthe sliding knob is shifted.

The effect of the invention is considerable in a dryshaving apparatusprovided with a hair-clipping device in which the shaving head has anappreciable height and the cutting members of the hair-clipping devicemay be raised to the level of the cooperating shaving members.

The ease of manipulation of the hair-clipping device is increased whenthe pin is mounted in the sliding knob which is adapted to slide in thedirection of displacement of the cutter system.

The invention if further characterized in that the pin, which is adaptedto be shifted by the sliding knob, is coupled to a pivoting lever havingunequal arms which intersect at an angle. The longer arm which isconnected to the cutter system, in the extended position of the cuttersystem extends substantially in the direction of displacement of thecutter system, and in the retracted position extends substantially in adirection at right angles thereto. The shorter arm of this lever issupported by a spring, the tension of which varies during thedisplacement of the cutter system between the said positions, becauseduring the sliding of the sliding knob through the sliding distance,this spring is operated by the pin so as to be given a higher tensionduring the first part of this sliding movement. At the beginning of thesecond part of the sliding movement the spring, which then is under thehigher tension, is suddenly permitted to relax. This results in anappreciable increase of the stroke.

A preferred embodiment using one pin is characterized in that the pinforms the pivot of the unequalarmed lever, the unequal arms of whichintersect at an obtuse angle, the longer arm being provided with aprojection which is slidable in a slot in the cutter system. In thisembodiment the stroke increase is achieved by an arrangement of simpleconstruction which may readily be manufactured by mass-productionmethods.

Another preferred embodiment using two pins is characterized in thateach of the two pins mounted in the sliding knob is journalled in a bar,each bar being hinged to the shorter arm of an unequal-armed lever thearms of which intersect one another at an acute angle. Each of thelonger arms of these two levers are hinged to one end of an extensionthe other end of which is connected to the cutter system, theseextensions being substantially aligned with the longer arms in theextended position and extending substantially parallel thereto in theretracted position.

This preferred embodiment provides a firmer mounting of the cuttersystem of the hair-clipping device, since in the extended position thecutter system is supported in two points by the rigidly arrangedextensions.

The invention will now be described more fully with reference to theaccompanying diagrammatic drawings of two preferred embodiments, inwhich like elements are designated by corresponding reference numeralsand in which irrelevant parts have been omitted, while furtheradvantageous details will manifest themselves.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a sectional view of apreferred embodiment with the cutter system of the hair clipping devicein the extended position, taken in the plane in which the cutters ofthis system move relative to one another,

FIG. 2 is a longitudinal sectional view taken at right angles to thesectional plane of FIG. I on the line Il-II of FIG. 1,

FIG. 3 is a cross-sectional view of the hair-clipper casing taken on theline IIIIII of FIG. 1,

FIG. 4 is a front elevation of the hair-clipper casing of a preferredembodiment with the hair-clipping cutter system in the extendedposition,

FIG. 5 is a sectional view taken on the line V-V of FIG. 4, and

FIG. 6 is a sectional view of the hair-clipper casing of FIG. 4 taken inthe plane in which the hair-clipping cutters move relatively to oneanother.

DESCRIPTION OF THE PREFERRED EMBODIMENT A cutter system 1 of ahair-cutting device 2 is displaceable relative to shave housing H in adirection at right angles to the direction of movement of the cutters 1Aand 1A of the system 1 in a hair-clipper casing 3. The cutter system 1is provided with an envelope 4 which follows the movement of the cuttersystem 1. The displacement of the cutter system 1 is simultaneous withthe sliding movement of a sliding knob 5 over an outer wall of thehair-clipper casing 3, the direction of this sliding movement beingparallel to the direction of the displacement of the cutter system 1.

In the sliding knob 5 of the preferred embodiment shown in FIGS. 1, 2and 3 there is mounted a pin 6 which also forms the pivot of anunequal-armed pivoting lever 7 which is pivotable in the plane in whichthe cutters 1A and 1A of the system 1 move relative to one another. Themovable cutter pivot about axis 1C, as actuated by lever 13 on pivot arm1D. The arms of the lever 7 intersect at an obtuse angle.

In the extended position the shorter arm 8 of the lever 7 is resilientlysupported by a spring 9 arranged in the hair-clipper casing, and in theretracted position of the cutter system this spring 9 also resilientlysupports the shorter arm 8 of the lever 7, which engagement may bereferred to as a spring engagement with bistable equilibrium.

The longer arm 10 of the lever 7 is provided at the end remote from thepivot 6 with a projection l 1 which is slidingly shiftable in a slot 12formed in the cutter system 1, preferably in the envelope 4. The end ofthe shorter arm 8 of the lever 7 remote from the pivot 6 is alsoprovided with a projection 13 which is slidingly shiftable in a slot 14formed in a wall of the hair-clipper casing 3. The slots 14 and 12extend substantially parallel to one another in a directionsubstantially at right angles to the direction of displacement of thecutter system 1. If now, starting from the situation shown in FIGS. 1and 2, the sliding knob is moved downwardly through a distance c (seeFIG. 2) the following changes will be produced.

During this sliding movement, the longer arm 10 of the lever 7 describesan arc b (see FIG. 1), while the projection 11 moves in the slot 12 fromright to left viewed in the plane of the drawing, and in doing sodisplaces the cutter system 1 through a distance a from an extendedposition to a retracted position, the distance a being appreciablygreater than the distance c. During this sliding movement the projection13 of the shorter arm 8, viewed in the plane of the drawing, will firstmove from left to right in the slot 14 and then from right to left, sothat the final position of the projection 13 willbe about the same asits initial position.

During the first part of the sliding movement of the sliding knob 5 theprojection 13 will increase the tension of the spring 9, this tensionbeing a maximum at the instant at which the pin 6 and the projection 13are at the same level, after which on further downward movement of thesliding knob 5 the spring will relax, so that the cutter system 1 duringthe second part of this sliding process will move with a highlyaccelerated movement. When the cutter system is moved from the retractedposition to the extended position by means of the sliding knob 5, thesaid process will take place in reverse order, giving the impressionthat the hairclipping cutter system 1 springs from the casing 3.

In the preferred embodiment shown in FIGS. 4, 5 and 6, the cutter systemof the hairclipping device 22 is again displaceable through a distancea, while the sliding knob 25 operating the cutter system is shiftablethrough an appreciably smaller distance c. In this embodiment there aremounted in the sliding knob 25 two pins 26 and 26' which also form thepivots about which two auxiliary bars 15 and 15' are pivotable. Theseauxiliary bars 15 and'lS' are hinged to shorter arms 28 and 28' of thetwo unequal-armed levers 27 and 27 which are arranged on the same leveland in each of which the arms intersect at an acute pivoting angle.These levers 27 and 27' are pivotable in the cutting plane of thehair-clipping cutters about two pivots 16 and 16' mounted in thehair-clipper casing 23. During the pivotal movement of the levers 27 and27 their longer arms and 20' move either towards or away from oneanother.

A spring 29, which preferably takes the form of a wre spring, istensioned between two pins 17 and 17 in the shorter arms 28 and 28' ofthe levers 27 and 27'. The longer arms 20 and 20' are hinged to twoextensions 18 and 18' the ends of which remote from the hinge connectionare connected to the cutter system 1. In the extended position of thecutter system, in which the spring 29 resiliently supports the shorterarms 28 and 28, these arms 28 and 28' are maintained in a lockedposition, since each of the longer arms 20 and 20' forms a rigid unitwith the respective extension 18 and 18. When in the situation shown inFIG. 6 the sliding knob 25 is shifted downwardly, the pins 26 and 26'with the bars 15 and 15 press against the ends of the spring 29, so thatthis spring 29 will be curved more tightly and hence will be under ahigher tension. The pins 17 and 17 will move downwardly and towards eachother until the highest tension of the spring is reached, which isobtained when the pins 17 and 17 are at the same level as are the pivotsl6 and 16', after which at the commencement of further downward shiftingof the sliding knob 25 the spring 29 will suddenly be relaxed,entraining the shorter arms 28 and 28'. As a result, the longer arms 20and 20 are pivoted inwardly to the positions denoted by 20a and 20'a,the extensions 18 and 18 assuming the positions denoted by 18a and l8'a.

When, with the cutter system retracted, the sliding knob is shiftedupwards, the spring will first be given a higher tension from theposition 29a and then, in the second half of the sliding movement, willsuddenly be permitted to relax, so that the cutter system willeffectively spring from the casing 20.

What is claimed is:

1. A hair-clipping device for combination with a dry shaver, the devicehaving a first part fixed relative to said shaver and a second partdisplaceable linearly between retracted and extended positions relativeto said first part, a bell-crank lever having a pivot axis and havingunequal length, short and long arms, the first and second partsrespectively having first and second slots therein, the end of the shortarm slidably engaging said first slot and the end of the long armengaging the second slot, and actuating means engaging said bell crankat its pivot axis, this means being movable linearly in the samedirection of movement as said second part from said retracted to saidextended positions, whereby said linear movement of the actuating meansand bell crank moves the second part a greater linear distance in thesame direction.

2. Apparatus according to claim 1 wherein said bell crank lever, (i)when in said extended position, has its long arm aligned generally inthe direction of displacement and (ii) when in retracted position hasits long arm aligned generally normal to said direction.

3. Apparatus according to claim 1 further comprising spring meanscarried by said device to contact and urge said short arm selectively toone of said two retracted and extended positions this spring engagementthus being in bi-stable equilibrium.

4. Apparatus according to claim 1 wherein said short and long armsdefine an obtuse angle between them.

5. A hair-clipping device for combination with a dry shaver, the devicehaving a first part fixed relative to said shaver and a second partdisplaceable linearly between retracted and extended positions relativeto said first part, a lever having a pivot point and first and secondarms which extend from said point and which engage said first and secondparts respectively, actuating means engaging said lever, this actuatingmeans being movable linearly and thereby moving and pivoting said leverwhose second arm moves said second part between said retracted andextended positions a greater linear distance than and in the samedirection as linear movement of the actuating means.

pivot point, this means being movable linearly and thereby moving thepivot point of the lever only linearly, and pivoting said lever whosesecond arm moves said second part between said retracted and extendedpositions a greater linear distance than linear movement of theactuating means and bell crank pivot point.

I UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent rim-Dated December 25, 1 973 Inventor) JAN 15E BOER; PETRUS JOZEPHUSJOHANNES VAES It is certified that error appears in the above-identifiedpatent and that said Letters Patent are hereby corrected as shown below:

In the T tle;

The Priority- Should read as follows:

Netherlands 7007687 May 28, 1970 Col. 3, line 61, "wre" should be--wire--- Claim 6, lir1e'8 "'of" should be --at-- signe and sealed this18th day of June 197L (SEAL) Atte'st:

EDWARD M.FLET 2HER,"JR. Attesting Officer 0. MARSHALL DANN Commissionerof Patents

1. A hair-clipping device for combination with a dry shaver, the devicehaving a first part fixed relative to said shaver and a second partdisplaceable linearly between retracted and extended positions relativeto said first part, a bell-crank lever having a pivot axis and havingunequal length, short and long arms, the first and second partsrespectively having first and second slots therein, the end of the shortarm slidably engaging said first slot and the end of the long armengaging the second slot, and actuating means engaging said bell crankat its pivot axis, this means being movable linearly in the samedirection of movement as said second part from said retracted to saidextended positions, whereby said linear movement of the actuating meansand bell crank moves the second part a greater linear distance in thesame direction.
 2. Apparatus according to claim 1 wherein said bellcrank lever, (i) when in said extended position, has its long armaligned generally in the direction of displacement and (ii) when inretracted position has its long arm aligned generally normal to saiddirection.
 3. Apparatus according to claim 1 further comprising springmeans carried by said device to contact and urge said short armselectively to one of said two retracted and extended positions thisspring engagement thus being in bi-stable equilibrium.
 4. Apparatusaccording to claim 1 wherein said short and long arms define an obtuseangle between them.
 5. A hair-clipping device for combination with a dryshaver, the device having a first part fixed relative to said shaver anda second part displaceable linearly between retracted and extendedpositions relative to said first part, a lever having a pivot point andfirst and second arms which extend from said point and which engage saidfirst and second parts respectively, actuating means engaging saidlever, this actuating means being movable linearly and thereby movingand pivoting said lever whose second arm moves said second part betweensaid retracted and extended positions a greater linear distance than andin the same direction as linear movement of the actuating means.
 6. Ahair-clipping device for combination with a dry shaver, the devicehaving a first part fixed relative to said shaver and a second partdisplaceable only linearly between retracted and extended positionsrelative to said first part, a bell crank lever having first and secondarms which extend from said pivot and which slidably and pivotablyengage said first and second parts respectively, actuating means whichengage said lever of its pivot point, this means being movable linearlyand thereby moving the pivot point of the lever only linearly, andpivoting said lever whose second arm moves said second part between saidretracted and extended positions a greater linear distance than linearmovement of the actuating means and bell crank pivot point.